NASA convinced it can find Earth-like planets

Emma Woollacott, 7th August 2009

Washington, DC - The Kepler Space Telescope has shown itself capable of finding Earth-like planets - if they exist - by detecting the atmosphere of a known gas giant.

The discovery was made just ten days after launch, even before the calibration and data analysis software were finished.

"As NASA's first exoplanets mission, Kepler has made a dramatic entrance on the planet-hunting scene," said Jon Morse, director of NASA's Science Mission Directorate's Astrophysics Division. "Detecting this planet's atmosphere in just the first 10 days of data is only a taste of things to come. The planet hunt is on!"

Kepler will spend the next three-and-a-half years searching for planets as small as Earth, including those that orbit stars in a warm zone where there could be water. It will do this by looking for periodic dips in the brightness of stars, which occur when orbiting planets transit, or cross in front of, the stars.

The observations were collected from a planet called HAT-P-7, known to transit a star located about 1,000 light years from Earth. The planet orbits the star in just 2.2 days and is 26 times closer than Earth is to the sun.

Kepler team members say the new data indicates that the mission is indeed capable of finding Earth-like planets, if they exist. The light variation observed was just one and a half times what is expected for a transit caused by an Earth-sized planet, indicating that Kepler would be sensitive enough to observe this.

"This early result shows the Kepler detection system is performing right on the mark," said David Koch, deputy principal investigator of NASA's Ames Research Center. "It bodes well for Kepler's prospects to be able to detect Earth-size planets."